WASHINGTON -- Republican Senator and Tea Party favorite Jim DeMint (R-S.C.) said on Sunday that Treasury Secretary Timothy Geithner has been "irresponsible" in talking about the debt limit, arguing the federal government could continue into August without a debt ceiling increase and not default on its loans.

"I think Secretary Geithner has been irresponsible, he's playing chicken little here," he said on "Fox News Sunday." "The fact is, we will pay our debts if it's the last dollar we have."

DeMint and several other Republicans have argued that the government would not default on its loans if the debt limit is not increased by Aug. 2, which the Treasury set as the "drop-dead" date after which the government will run out of options to pay off its loans. The debt limit, currently set at $14.29 trillion, was reached on May 16, but the Treasury Department has taken "extraordinary measures" to keep the government from defaulting on its loans until Aug. 2.

Yet DeMint rejected the idea that the government would default on that date, saying it could use incoming revenues to pay off debts. He said Social Security and Medicare payments would also go out on time even if there was no debt deal by August.

"There are enough assets in Social Security and Medicare to pay the benefits of those programs for several years," he said. "Other programs can be funded from tax revenue. There certainly will be disruption, but this is not a deadline we should rush and make a bad deal and do something that cuts benefits from seniors without giving them better choices."

Geithner refuted that claim on CBS's "Face the Nation" Sunday, saying he and the president "have looked at all options" for dealing with the debt ceiling.

"I can say to you with total confidence we have no other option to buy more time for Congress," he said. "And they don't need more time. They know what it takes to get this done."